Cartridge for faucets having small plates of hard material and a metallic covering

ABSTRACT

A cartridge for faucets having some parts which are assembled in the cartridge to function as a guide, an element of support for a movable small plate of hard material, forming a part of the above mentioned guiding parts, at least one small plate of hard material operatively mounted and fixed in the cartridge, and at least one movable small plate mounted in the aforementioned element of support and adapted to be movable in relation to the fixed small plate in order to bring about the regulation of fluid flow and the proportion of mixing. At least one of the surfaces of the parts of plastic material, adapted to slide against the surface of other pieces of plastic material, is provided with a metal layer, preferably by chemical or electrochemical means. It is preferred that the metal cover is applied on an intermediate part having surfaces adapted to slide in contact with different parts of plastic material, and precisely on a guiding ring.

BACKGROUND OF THE INVENTION

I. Field of the Invention

The present invention relates to a cartridge adapted to be inserted inthe body of a faucet, including a guide, an element of support for amovable small plate of hard material positioned within the guidingparts, at least one small plate of hard material which is fixedlymounted in the cartridge, and at least one movable small plate mountedin the element of support and adapted to move against the fixed smallplate in order to effectuate the regulation of the rate of fluid flowand of the proportion of mixing.

II. Description of the Prior Art

In the usual construction, the element of support for the movable smallplate and the parts which function as a guide are made of plasticmaterial and their reciprocal sliding is facilitated by properly chosenplastic material and a lubricating grease. However, with time, thelubricating grease is expended, the plastic material loses itsself-lubrication, and an excessive friction begins to develop betweenthe parts which are subjected to a reciprocal sliding movement resultingin a clatter which is very unpleasant to the user. This inconveniencecan be overcome in certain constructions by inserting thin gaskets ofmetallic foil between the parts of plastic material which are subjectedto a reciprocal sliding movement. In fact, a proper choice of metallicmaterial permits the avoidance of the development of excessive frictionand of the noise which occurs with time when there is movement. However,the insertion of these gaskets has a relatively high cost, not only fortheir construction but because of the complications that they bring tothe assembly of the cartridge. Further, this is not even possible incertain cases; for example, when one of the parts has a lamellarstructure, an elevated structure or other structures which are destinedto stop the vibration and the noise of the water flow.

SUMMARY OF THE PRESENT INVENTION

The scope of the present invention is to obtain a cartridge of the typedescribed, in which the damaging phenomena of the prior known system isprevented by economical means and without introducing any complicationof assembly.

This goal can be attained, according to the present invention, byproviding at least one of the surfaces of the parts made of plasticmaterial adapted to be submitted to sliding against the surfaces ofother parts of plastic material, is provided with a thin metallicdeposit on the surface thereof.

In a way which is well known, this deposition can be done by chemical orelectrochemical means--previous sensitization of the surface, andeventual intermediate deposition of an adherent layer--and a similarprocess which has preferable results. However, the deposition of themetal layer on the gasket can also be done with other processes, forexample, through deposition under a vacuum. -. The metal used to formthe gasket layer can be chosen according to various criteria butchromium is particularly adapted for this function. The chromium layeris preferably applied on intermediate adherent layers of copper and/ornickel.

It is advantageous if only one of the two surfaces of the plastic partsadapted to slide in reciprocal contact is covered with metallicmaterial. From a functional standpoint, it does not matter if thecovering is applied to one or the other of the two cooperating surfaces.However, in the cases in which the couplings that one wants to line witha metallic layer are more than one, there is a particular advantageobtained by effectuating the covering on an intermediate part, which hasat least two surfaces and which are adapted to slide in contact withother parts of plastic material. In fact, in this way, the treatment ofone piece is sufficient to line two pairs of sliding surfaces; in manycases, this represents the total number of surface pairs of a cartridgewhich are important to the application of the invention. In particular,in the cartridges which have a revolving guide ring across which movesthe movable small plate of hard material, it is particularlyadvantageous to plate the principle surfaces of this guide ring withchromium.

Other objects, features and advantages of the present invention will beapparent from the following detailed description taken in connectionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

The present invention will be more fully understood by reference to thefollowing detailed description of a preferred embodiment of the presentinvention when read in conjunction with the accompanying drawing, inwhich like reference characters refer to like parts throughout the viewsand in which:

FIG. 1 is a cross-sectional perspective of a faucet embodying the flowcartridge of the present invention;

FIG. 2 is a partial cross-sectional perspective of the flow cartridge ofthe present invention taken along line II--II of FIG. 1;

FIG. 3 is a plan view of the guide ring of the invention viewed alongline III--III of FIG. 2; and

FIG. 4 is a plan view of the guide ring of the invention viewed alongline IV--IV of FIG. 2.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE PRESENT INVENTION

The faucet and the respective cartridge, described herein andillustrated in the drawing, are examples of known structures which aredescribed here for clearness of understanding only. However, it is to beunderstood that the application of the invention is not, in any way,limited to these particular types of faucets or cartridges.

The mixing faucet embodying the present invention and shown in FIG. 1includes body 1 at the bottom of which there are two flow passages 7 and8 through which the hot and cold water are respectively supplied andwhich communicate with parts 3 and 4 shown at the bottom of body 1 ofthe faucet. Body 2 has an internal rim adapted to house a cartridge, andforms a cylindrical chamber 2 which communicates with an outletpassageway which is not shown. The body 1 is closed by a cover 5 havinga sealing gasket 6.

The cartridge, which in its realized form represents a complete andinterchangeable cartridge, includes a cover 10 which forms an enclosureconstructed of plastic material and having axial mobility within thefaucet body 1. In this case, the enclosure 10 has a bottom 9 whichextends to form two sealed ports 11 and 12 which extend through theseals 3 and 4 of the faucet body I, which communicate with pipes, 7 and8, in which hot and cold water are supplied. The bottom of enclosure 10,on which the parts 11 and 12 are found, form the element of support forthe fixed plate 18 of hard material of the faucet. This makes a sealwith the bottom 9 due to gaskets 16 and 17, inserted in correspondingseats formed in the bottom 9 of the

enclosure 10. The plate 18 has two apertures corresponding to the ports11 and 12, for the passage of hot and cold water, respectively.

In contact with the fixed plate 18 a movable plate 19 of hard materialis mounted, supported by a control slide 20 that is guided in a way thatenables it to move within a guide ring 21, and also mounted in such away that it can revolve in enclosure 10. Not only the slide 20 but alsothe ring 21 are preferably made of plastic material. The ring 21 bearsagainst a semi-bearing 22 which is fixed at the mouth of enclosure 10and is also made of a plastic material. Further, the semi-bearing 22engages cover 5 which encloses the body of the faucet. Anothersemi-bearing 23 is positioned in cover 5, and between the semi-bearings22 and 23, an articulation sphere 25 is inserted with a sealing gasket24. The sphere 25 supports an arm 26 to which is connected a cap 28 witha control lever 29. Towards the inside, a second arm 27 is connected tosphere 25. This second arm 27, which is planar and functions like asmall key, is fixedly connected to control slide 20. This well-knownarrangement permits, by making lever 29 rotate and pivot variably, themovement of the control slide 20. As a result, the movable plate 19,which also moves and rotates variably when lever 29 is moved, slides androtates with respect to the fixed plate 18 in order to regulate thefluid flow that is supplied from the pipes 7 and 8 and mixes in thering-like chamber 2 from which a mixed flow is delivered.

The slide 20 moves in direct contact with the guide ring 21 which alsorotates in direct contact with the semi-bearing 22. There are,therefore, two cooperating surfaces of plastic material that can move inreciprocal contact. This movement takes place under considerablepressure. Due to the fact that the necessary pressure for an effectivecooperation of the movable plate 19 and fixed plate 18 is transmittedacross these surfaces, the pressure transmitted is notably greater thanthat which is needed for the cooperation between the small plates ofhard material. For this reason, a lubricating grease that one can insertat the moment that the cartridge is assembled between the members 20 and21, and 21 and 22, is gradually expended. On the other hand, the partsof plastic material, even if they are initially produced with thecharacteristics of auto-lubrification, with time lose thesecharacteristics because they operate in the presence of hot water. As aresult, a considerable friction is created between parts 20, 21 and 22.This friction hinders the movement of the faucet and further, themaneuvering of the faucet is accompanied with unpleasant clattering andvibrations.

The insertion of thin, metallic gaskets between parts 20, 21 and 22avoids this inconvenience, and this is possible to accomplish, but itmakes the operation of assembling the cartridge notably more complex anddelicate. Further, to obtain a favorable operation, one cannot use aplate of common stainless steel, but one must use, for example, a littleplate of chrome plated brass. All this reflects an acceptable butdifficult way to produce the cartridge, in terms of both the cost andthe configuration of production.

However, with the application of the present invention, the surfaces ofthe guide ring 21 that work in contact with the surfaces of slide 20 andsemi-bearing 23, are covered by a layer of metal of an adequate nature,preferably chromium. In this way, the control movements do not takeplace between surfaces of plastic material but between surfaces ofplastic material and metallic surfaces similar to the case in which ametallic plate is inserted between the parts. Further, assembly of thecartridge takes place in a way which completely corresponds to that of acartridge without metallic gaskets. Due to the fact that the proceduresof metallization of the plastic surfaces are up to date and sufficientlyeconomical, the cost of manufacturing the cartridge, according to thepresent invention, is not substantially increased with respect to acartridge without metallic gaskets, and results in a lower cost ascompared to that obtained with a cartridge which has metallic gasketsinserted.

As shown in FIGS. 2 and 4, the guide ring 21 presents a surface whichworks in contact with the semi-bearing 22, and this surface of the guidering is provided with a metallic covering 30. From this, a projection 34extends which cooperates with internal projections (not shown) of thesemi-bearing 22 in order to properly limit the field of rotation of theguide ring 21.

On the opposite side, the guide ring 21 peripherally includes aprotruding frame 31 which sets the boundaries for a frame in which theslide 20, which carries the movable plate 19, can move. Also, the ring21 has a window 32 in which a protrusion 20a of the slide 20, whichforms the place for the maneuvering key, extends. The surfaces betweenthe elevated frame 31 and the window 32 are also lined with a metalliccovering 33. Naturally, in the drawing, the thickness of the layers 30and 33, which if correctly represented in scale would not beperceivable, is exaggerated.

In this way, not only the movement of slide 20 against surface 33 of theguide ring 21, but also the sliding of surface 30 of the guide ring 21against the semi-bearing 22 occurs between plastic and metal materials.Further, with the proper selection of materials, a low frictioncoefficient and silent, regular movements can be obtained even in theabsence of lubrication and after an extended period of use.

The fact that the metallization is executed on the two surfaces, 30 and33, of ring 21 instead of on the corresponding surfaces of semi-bearing22 and, respectively, of slide 20 offers the advantage that only onecomponent of the cartridge is required to be submitted to themetallization treatment thereby reducing costs. Naturally, an eventualmetallization of other surfaces of the guide ring 21, other thansurfaces 30 and 33, does not cause any inconvenience. Rather, themetallization of the internal walls of the window 32 facilitates thesliding of the protrusion 20a of slide 20 and the metallization of theexternal surface, having the form of a mantle, or ring 21 facilitatesthe rotation of it inside the enclosure 10. However, these lastmovements are not critical because they occur without the application ofsubstantial pressure. Nevertheless, the piece 21 can be submitted tometallization without any precautions to protect part of its surfaces.This makes the operations of sensitization, adherent covering and finalchrome plating particularly simple, in the case in which themetallization is done with a chemical process followed by anelectrochemical process, as is usually done and is particularlyadvantageous when using plastic material.

It is important to note that the metallization is not hindered by acomplex configuration for the surface that must receive it. If it isrequired, the surface can have some lamellar configurations or otherconfigurations which facilitate to control premature closing and to stopnoise associated with the fluid flow.

The use of chromium to make the final metallization (preferably appliedon intermediate adherent layers of copper and/or nickel) offersexcellent results. However, other metals can be applied and, it must benoted, that consideration must be given to the thickness of the metallayer which must be very thin in order to be applied as thin layers inmetallization, and therefore, consuming a minimal quantity of metalwhich allows the use of more expensive metals without greatly increasingthe cost of production.

As aforementioned, the application of the invention is not linked to anyparticular configuration of the cartridge parts. The illustratedrealized form has not other goal but to furnish an example of completeactualization. Thus, for example, the cartridge could have a guide ringwhich does not revolve, or the slide that carries the movable platecould be guided by parts integrally formed with the enclosure with thecovering of the cartridge. Furthermore, the cartridge does notnecessarily have to be a true, proper, complete, interchangeablecartridge as a unit, but the invention can also be applied in cases inwhich the cartridge is made by an assembly of parts, which are insertedin the body of the faucet but which together do not form aninterchangeable unit.

The foregoing detailed description has been given for clearness ofunderstanding only and no unnecessary limitations should be understoodtherefrom as some modifications will be obvious to those skilled in theart without departing from the scope and spirit of the appended claims.

I claim:
 1. In a fluid flow control cartridge for a faucet having abody, the cartridge including a housing adapted to be inserted in thebody of the faucet, the housing having a slider element operativelyconnected to a control handle of the faucet for controlling slidingmovement of at least one movable plate of hard material with respect toat least one fixed plate of hard material to regulate fluid flow throughthe cartridge, the slider element positioned within guide means forlimiting the movement of the slider element, the slider element andguide means having cooperating selectively engageable surfaces, theimprovement comprising:bonding a layer of metallic material on thecooperating selectively engageable surface of at least one of the sliderelement and the guide means.
 2. The improved cartridge as defined inclaim 1 wherein said cooperating surface of at least one of the sliderelement and the guide means is sensitized prior to bonding of saidmetallic layer by intermediate deposition of at least one layer of anadherent.
 3. The improved cartridge as defined in claim 2 wherein saidbonding of said metallic layer is done through chemical depositionmeans.
 4. The improved cartridge as defined in claim 2 wherein saidbonding of said metallic layer is done through electrochemicaldeposition means.
 5. The improved cartridge as defined in claim 2wherein said bonding of said metallic layer is done under a vacuum. 6.The improved cartridge as defined in claim 2 wherein said metallic layerconsists of a chrome material.
 7. The improved cartridge as defined inclaim 6 wherein said intermediate adherent layer consists of a coppermaterial.
 8. The improved cartridge as defined in claim 6 wherein saidintermediate adherent layer consists of a nickel material.
 9. Theimproved cartridge as defined in claim 2 wherein the cartridge includesa semi-bearing engaging the guide means, the guide means slidablymovable against the semi-bearing, the guide means and the semi-bearinghaving cooperating engageable surfaces, the guide means having saidengageable surface deposited with a layer of metallic material.
 10. In afluid flow control cartridge for a faucet having a body, the cartridgeincluding a housing adapted to be inserted in the body of the faucet,the housing having a slider element operatively connected to a controlhandle of the faucet for controlling sliding movement of at least onemovable plate of hard material with respect to at least one fixed plateof hard material to regulate fluid flow through the cartridge, theslider element positioned within guide means for limiting the movementof the slider element, the slider element and guide means havingcooperating selectively engageable surfaces, the improvementcomprising:depositing a layer of metallic material on the cooperatingselectively engageable surface of at least one of the slider element andthe guide means, said cooperating surface of at least one of the sliderelement and the guide means being sensitized prior to deposition of saidmetallic layer by intermediate deposition of at least one layer of anadherent.
 11. In a fluid flow control cartridge for a faucet having abody, the cartridge including a housing adapted to be inserted in thebody of the faucet, the housing having a slider element operativelyconnected to a control handle of the faucet for controlling slidingmovement of at least one movable plate of hard material with respect toat least one fixed plate of hard material to regulate fluid flow throughthe cartridge, the slider element positioned within the guide means forlimiting the movement of the slider element, the slider element andguide means having cooperating selectively engageable surfaces, theimprovement comprising:bonding deposition of a layer of metallicmaterial on the cooperating selectively engageable surface of at leastone of the slide element and the guide means.
 12. The improved cartridgeas defined in claim 11 wherein said cooperating surface of at least oneof the slider element and the guide means is sensitized prior to bondingdeposition of said metallic layer by intermediate bonding deposition ofat least one layer of a metallic adherent.